*I know he has these fetishes and i do accept them. But there seems to be no give and take or good will towards my desires.
My exH was exactly the same - so maybe it's me and i'm just too demanding.*
Read this - what you wrote - and see if it makes sense. It doesn't. There is no give and take, or goodwill towards your desires, but you are being too demanding?
It's not being too demanding to want, even expect, give and take. That's what makes it a relationship. Without give and take it's not a relationship.
Also I asked earlier if your dp is a porn user, and you said no. But then you said he is going on fetish sites every day. The reason I asked about porn is it can 'wire' men to need certain types of sexual stimuli to physically achieve erection/orgasm. There is a pretty tragic syndrome emerging of young men who should be virile and are actually unable to have 'vanilla' sex in their relationships (and often heartbroken about it) because repeated exposure to more extreme sexual images and masturbation over them has made them unable, physically, to get aroused without them. Google 'porn and erectile dysfunction' and there is lots of information.
Fetish sites are no different, qualitatively. Your dp associates sexual satisfaction with the fetish and feeds this by going on these sites all the time. He has probably affected the reward pathways in his brain in such a way that he isn't able to get turned on by more conventional lovemaking. Hence the lack of enthusiasm.
When you've got a baby you won't have time to have 4 hour sessions. You will be lucky if you have time to dry your hair with a hairdryer, iron a single shirt, unload the dishwasher or chat to someone for half an hour on the phone.
It's really important that you address this problem, OP. Your needs are not being met here and you are not being demanding wanting things to change. But your partner has to meet you halfway.
Men who have lost their mojo for vanilla sex (or even soft touch) can usually only get it back with effort and patience. Your Dp's brain is wired for fetish scenarios and he's lost interest. It sounds like he has huge problems with loving touch, kissing etc and you are going to struggle to meet halfway.
I think you should maybe seek some professional advice - maybe from a sex therapist and work out what you want from this relationship going forward. You sound like you are being killed off inside by this mechanistic, impersonal, role playing and want some proper intimacy at least some of the time. You are getting none, at least not in the context of your sexual relationship.
Baby will come along and your sexual appetites will change even more, IME. You will have even less interest in these practices you describe - having children softens us - and however deeply you love you partner, those feelings will have to sit alongside another, more visceral love that you will feel for your child.
Not at all judgemental about porn/fetishes, etc, for the record. If everyone's happy with what they are doing, anything is OK. But you are not happy, and that's what's not OK. You have big problems and you would be wise to address them now, because it's going to get worse. And you have every right to your needs, just as much as your partner has a right to his. Don't forget that.